diff --git a/tools/build/build.go b/tools/build/build.go
new file mode 100644
index 000000000..7a334b5ad
--- /dev/null
+++ b/tools/build/build.go
@@ -0,0 +1,238 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"runtime"
+	"strings"
+	"time"
+)
+
+var (
+	targetOS   = flag.String("os", runtime.GOOS, "Target OS of this build.")
+	targetArch = flag.String("arch", runtime.GOARCH, "Target CPU arch of this build.")
+	archive    = flag.Bool("zip", false, "Whether to make an archive of files or not.")
+
+	GOPATH   string
+	repoRoot string
+)
+
+type OS string
+
+const (
+	Windows = OS("windows")
+	MacOS   = OS("darwin")
+	Linux   = OS("linux")
+)
+
+type Architecture string
+
+const (
+	X86   = Architecture("386")
+	Amd64 = Architecture("amd64")
+	Arm   = Architecture("arm")
+	Arm64 = Architecture("arm64")
+)
+
+func getRepoVersion() (string, error) {
+	revHead, err := exec.Command("git", "rev-parse", "HEAD").Output()
+	if err != nil {
+		return "", err
+	}
+	version, err := exec.Command("git", "name-rev", "--tags", "--name-only", strings.TrimSpace(string(revHead))).Output()
+	if err != nil {
+		return "", err
+	}
+	verStr := strings.TrimSpace(string(version))
+	if strings.HasSuffix(verStr, "^0") {
+		verStr = verStr[:len(verStr)-2]
+	}
+	if verStr == "undefined" {
+		verStr = "custom"
+	}
+	return verStr, nil
+}
+
+func getOS() OS {
+	if targetOS == nil {
+		panic("OS is not specified.")
+	}
+	osStr := strings.ToLower(*targetOS)
+	if osStr == "windows" || osStr == "win" {
+		return Windows
+	}
+	if osStr == "darwin" || osStr == "mac" || osStr == "macos" || osStr == "osx" {
+		return MacOS
+	}
+	if osStr == "linux" || osStr == "debian" || osStr == "ubuntu" || osStr == "redhat" || osStr == "centos" {
+		return Linux
+	}
+	panic("Unknown OS " + *targetOS)
+}
+
+func getArch() Architecture {
+	if targetArch == nil {
+		panic("Arch is not specified.")
+	}
+	archStr := strings.ToLower(*targetArch)
+	if archStr == "x86" || archStr == "386" || archStr == "i386" {
+		return X86
+	}
+	if archStr == "amd64" || archStr == "x86-64" || archStr == "x64" {
+		return Amd64
+	}
+	if archStr == "arm" {
+		return Arm
+	}
+	if archStr == "arm64" {
+		return Arm64
+	}
+	panic("Unknown Arch " + *targetArch)
+}
+
+func getSuffix(vos OS, arch Architecture) string {
+	suffix := "-custom"
+	switch vos {
+	case Windows:
+		switch arch {
+		case X86:
+			suffix = "-windows-32"
+		case Amd64:
+			suffix = "-windows-64"
+		}
+	case MacOS:
+		suffix = "-macos"
+	case Linux:
+		switch arch {
+		case X86:
+			suffix = "-linux-32"
+		case Amd64:
+			suffix = "-linux-64"
+		case Arm:
+			suffix = "-linux-arm"
+		case Arm64:
+			suffix = "-linux-arm64"
+		}
+
+	}
+	return suffix
+}
+
+func createTargetDirectory(version string, vos OS, arch Architecture) (string, error) {
+	suffix := "-custom"
+	if version != "custom" {
+		suffix = getSuffix(vos, arch)
+	}
+	targetDir := filepath.Join(GOPATH, "bin", "v2ray"+suffix)
+	if version != "custom" {
+		os.RemoveAll(targetDir)
+	}
+	err := os.MkdirAll(targetDir, os.ModeDir|0777)
+	return targetDir, err
+}
+
+func getTargetFile(vos OS, arch Architecture) string {
+	suffix := getSuffix(vos, arch)
+	if vos == "Windows" {
+		suffix += ".exe"
+	}
+	return "v2ray" + suffix
+}
+
+func normalizedContent(content []byte, vos OS) []byte {
+	str := strings.Replace(string(content), "\r\n", "\n", -1)
+	if vos == Windows {
+		str = strings.Replace(str, "\n", "\r\n", -1)
+	}
+	return []byte(str)
+}
+
+func copyConfigFiles(dir string, version string, vos OS, arch Architecture) error {
+	clientConfig, err := ioutil.ReadFile(filepath.Join(repoRoot, "release", "config", "vpoint_socks_vmess.json"))
+	if err != nil {
+		return err
+	}
+	clientConfig = normalizedContent(clientConfig, vos)
+	clientConfigName := "vpoint_socks_vmess.json"
+	if vos == Windows || vos == MacOS {
+		clientConfigName = "config.json"
+	}
+	err = ioutil.WriteFile(filepath.Join(dir, clientConfigName), clientConfig, 0777)
+	if err != nil {
+		return err
+	}
+
+	if vos == Windows || vos == MacOS {
+		return nil
+	}
+
+	serverConfig, err := ioutil.ReadFile(filepath.Join(repoRoot, "release", "config", "vpoint_vmess_freedom.json"))
+	if err != nil {
+		return err
+	}
+	serverConfig = normalizedContent(serverConfig, vos)
+	err = ioutil.WriteFile(filepath.Join(dir, "vpoint_vmess_freedom.json"), serverConfig, 0777)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+func buildV2Ray(targetDir, targetFile string, version string, vos OS, arch Architecture) error {
+	ldFlags := "-s"
+	if version != "custom" {
+		year, month, day := time.Now().UTC().Date()
+		today := fmt.Sprintf("%04d%02d%02d", year, int(month), day)
+		ldFlags = ldFlags + " -X github.com/v2ray/v2ray-core.version=" + version + " -X github.com/v2ray/v2ray-core.build=" + today
+	}
+	target := filepath.Join(targetDir, targetFile)
+	fmt.Println("Building to " + target)
+	cmd := exec.Command("go", "build", "-o", target, "-compiler", "gc", "-ldflags", "\""+ldFlags+"\"", "github.com/v2ray/v2ray-core/release/server")
+	cmd.Env = append(cmd.Env, "GOOS="+string(vos), "GOARCH="+string(arch))
+	cmd.Env = append(cmd.Env, os.Environ()...)
+	_, err := cmd.Output()
+	return err
+}
+
+func main() {
+	flag.Parse()
+
+	v2rayOS := getOS()
+	v2rayArch := getArch()
+
+	if err := os.Chdir(repoRoot); err != nil {
+		fmt.Println("Unable to switch to V2Ray repo: " + err.Error())
+		return
+	}
+	version, err := getRepoVersion()
+	if err != nil {
+		fmt.Println("Unable to detect V2Ray version: " + err.Error())
+		return
+	}
+	fmt.Printf("Building V2Ray (%s) for %s %s\n", version, v2rayOS, v2rayArch)
+
+	targetDir, err := createTargetDirectory(version, v2rayOS, v2rayArch)
+	if err != nil {
+		fmt.Println("Unable to create directory " + targetDir + ": " + err.Error())
+	}
+
+	targetFile := getTargetFile(v2rayOS, v2rayArch)
+	err = buildV2Ray(targetDir, targetFile, version, v2rayOS, v2rayArch)
+	if err != nil {
+		fmt.Println("Unable to build V2Ray: " + err.Error())
+	}
+
+	err = copyConfigFiles(targetDir, version, v2rayOS, v2rayArch)
+	if err != nil {
+		fmt.Println("Unable to copy config files: " + err.Error())
+	}
+}
+
+func init() {
+	GOPATH = os.Getenv("GOPATH")
+	repoRoot = filepath.Join(GOPATH, "src", "github.com", "v2ray", "v2ray-core")
+}